Abstract
This paper proposes a new quality-in-use model for measuring user interface design quality, and is intended specifically for mobile devices. The proposed model is based on the international standard ISO 9126-4 [ISO/IEC TR 9126-4:2004] and can be adapted to various applications. The quality-in-use factors of effectiveness, productivity, efficiency, safety, and satisfaction are redefined to reflect the ways in which mobile devices are used, and the contexts in which they are used. A new factor, task navigation, is proposed to measure the cognitive load on the user when he or she interacting with the interface across different platforms. Our objectives include theoretical and empirical validation of the proposed measurement model.